Abstract: A hanger adapter utilized in hanging fixtures on an inclined ceiling in conjunction with a hanger assembly and a fixture attachment assembly. The hanger adapter provides for the attachment of the hanger and fixture attachment assemblies to same at a position laterally offset from each other so as to effect a substantial alignment of the center of gravity of the fixture and the main axis of the hanger assembly with respect to vertical in an installed position. The hanger adapter has a plate with position indicators, each of which corresponds to a particular selectable, predetermined lateral offset which effects such a substantial alignment for its corresponding preselected angle of ceiling incline and the configuration of the hanger and fixture attachment assemblies utilized.

Abstract: The present invention provides a ceiling-mounted or wall-mounted light fixture, an enclosure which is releasably securable to that fixture, interacting supporting surfaces on that enclosure and on that fixture which permit rotation of that enclosure relative to that fixture to secure that enclosure to that fixture or to release that enclosure from that fixture, a mold-smooth fixture-receiving surface on that enclosure, and a die-cut enclosure-engaging surface on that fixture which will always provide a smooth engagement between itself and the mold-smooth fixture-receiving surface on that enclosure.

Abstract: A ceiling frame is provided for a lighting fixture. The ceiling is of the type made of plaster panels commonly known as dry wall, wallboard, plaster board, or gypsum board. A rectangular opening is made in the plaster panels between rafters and the lighting fixture is suitably mounted on the ceiling above the panels. The ceiling frame includes side frame members having vertical flanges positioned adjacent the edges of the ceiling panels at the rectangular opening and horizontal flanges extending outwardly from the opening along the lower surfaces of the panels. The horizontal flanges are affixed to the panels by pop rivets or the like which also extend through upper horizontal flanges or brackets adjacent the upper surfaces of the panels. The ceiling frame also includes two end frame members of similar design but affixed to the ceiling panels adjacent the end edges of the opening by rivets and brackets.

Abstract: A convertible suspension mounting system for ceiling fans having a disk-shaped fixing support for being secured on the ceiling surface, a housing body of a bowl shape connected to the fixing support, a connecting device flexibly coupled with the housing body at one end and screw-connected to a pipe fitting of a ceiling fan structure. The connecting device includes a tubular connecting member with screw threads and a through hole respectively formed at each end, a circular coupling member screw-connected to the connecting member at the upper portion, and an axially flexible pipe sleeve fastened between the circular coupling member and the bottom side of the housing body with the upper portion of the connecting member flexibly received therein, so that the connecting member is provided with an axial deviation for adapting to various ceiling surface conditions, and the suspension system can be conveniently converted into a direct coupling system without the connecting device.

Abstract: A swivel canopy for hanging electrical fixtures is disclosed having means whereby the installation of the canopy can be tested prior to use in order to insure that it has been properly installed and that it will supply the requisite support and stability during the use thereof. The means provided is comprised of a substantially U-shaped resiliently, outwardly biased spring member which is disposed through the suspension conduit. In a preferred embodiment, the means provided is comprised of a pair of arcuately-shaped, resiliently-outwardly biased spring retainers which are diametrically positioned about the suspension conduit.

Abstract: A support leg (14) is attached to a ceiling structure (10) by means of a threaded stud (12) which mates with a threaded opening (18) in an insert (16) which is swage connected to the upper end of the support leg (14). A flat bar (20) is attached to the lower end of the support leg (14) so that it extends horizontally and makes a "T" with the support leg (14). An expansion clamp assembly (22) is carried by the bar (20). This assembly (22) is plugged into the tubular lower end portion (24) of the support leg (14). The uppermost part of the assembly (22) is a T-nut (48). The head (50) of the nut (48) includes a plurality of struck out barbs (76) having points (74) which penetrate into and grip the inner sidewall of the socket (24) when the assembly (22) is inserted into the socket (22). This secures the nut (48) against rotation.

Abstract: A ceiling fan mounting assembly includes a readily installed specially shaped hanger bracket which provides direct high load and torque resistant support for the ceiling fan assembly, as well as providing support for the electrical junction box.

Abstract: A hanger assembly for one-handed mounting between opposing surfaces of wall studs or ceiling joists in normally inaccessible places. The hanger assembly has telescoping elements with toothed ends which are adapted to pierce into wall studs or ceiling joints when the elements are extended. The telescoping elements are spread apart by planting starter teeth on the follower element into a stud or joist and then turning a main body element until the end teeth of the follower element and the end teeth of the main body unit are fully embedded. The follower element is preferably spring loaded so as to provide the hanger assembly with a following or self-adjusting action. The self-adjusting action causes the hanger assembly to adapt to deformations of the wall studs or ceiling joists and to retain the compressive attachment integrity of the hanger assembly.

Abstract: This loudspeaker mounting system provides an enclosure (10) which is intended for installation into a drywall ceiling (12). The enclosure (10) includes an upper wall (16), and an annular lower flange (18) interconnected by a cylindrical sidewall (20). The sidewall includes a circumferentially spaced generally tee-shaped slots (30) each receiving an individual support bracket member (32) having a generally ell-shaped forward portion (54) and a slotted rearward portion (56). Inwardly projecting threaded fasteners (52) are attached to the sidewall adjacent each slot (30) to receive the slotted transverse portion (56). When the bracket member forward portions (54) are inserted into the sidewall (20) the bracket members can be guided into engagement with the ceiling (12) so that the ceiling is sandwiched between the flange (18) and the individual bracket members (32).

Abstract: A rod assembly adapted to be mounted underneath a shelf or ceiling having an elongated support bar for hanging thereon clothes or the like from hangers. The bar is supported at its mid position by a support member which provides firm support but allows the hangers to pass thereover without dislodgement if the hanger strikes the support member.

Abstract: A support leg (14) is attached to a ceiling structure (10) by means of a threaded stud (12) which mates with a threaded opening (18) in an insert (16) which is swage connected to the upper end of the support leg (14). A flat bar (22) is attached to the lower end of the support leg (14) so that it extends horizontally and makes a "T" with the support leg (14). An expansion clamp assembly (28, 36, 40, 44, 50, 46, 74) is carried by the bar (22). This assembly is plugged into the tubular lower end portion (26) of the support leg (14). Wing portions (58) of a nut wing washer (50) are deflected by the insertion of the assembly into the tubular portion (26), and edges (62) of the wings (58) are biased into a tight gripping contact with the inner tubular portion (26). This secures the nut wing washer (50) and a nut ( 46) against rotation. Then, the member (22) is rotated, relative to the support leg (14), causing a relative endwise movement of a stud (28) carried by the member (22) into the nut (46).

Abstract: Apparatus for mounting a fan or similar device to the ceiling of a building or mobile home, the invention also includes methods for installation of the apparatus and encompasses related embodiments of the apparatus. The several apparatus embodiments of the invention find utility within differing environments within which the apparatus is to be installed, certain of the embodiments being particularly useful for mounting a fan to the ceiling of a mobile home or the like and certain other embodiments being configured to facilitate mounting within the structural confines of standard building structures having one or more levels. In an embodiment useful for buildings having clearance above ceiling joists, the invention comprises an elongated bar configured to fit over upper surfaces of adjacent joists and to suspend an electrical outlet box beneath the bar with the fan being supported on a hook, double prong mounting bracket, or a hanging bracket.

Abstract: A system for mounting a ceiling fan is disclosed in which the ceiling fan is mounted relatively close to the ceiling of a conventional residential room having a ceiling height of about eight feet, in which the rotational plane of the fan blades is about seven or more feet from the floor.

Abstract: A device is provided for attaching a depending unit (e.g., a poster) to a ceiling wherein the latter includes a support having an exposed flange. The depending unit has a thin upper peripheral segment with means for adjustment from a first mode to a second mode. The device has an elongated member provided with an elongated interior cavity accessible through an elongated narrow opening formed in the exposed surface thereof. The opening is sized to permit the unit upper peripheral segment to pass therethrough only when the means is in the first mode. When the unit upper peripheral segment is disposed within the cavity of the elongated member, the means assumes a second mode whereby the elongated member and said unit are retained in attached relation. The device is provided with an element which engages a concealed surface portion of the elongated member and coacts with the exposed flange of the ceiling support and secures the elongated member thereto.

Abstract: An electric ceiling fan of minimum practical axial depth for conserving needed head room includes a wheel-like frame; a fan motor nested therein; a fan blades assembly nested around and driven by such motor; a shallow support adapted to be attached directly to a ceiling; shallow hanger arms pivotally suspending the frame from the support for generally varying the air flow; a shallow, air pervious upper guard enclosing the motor and fan blades assembly; a step motor nested in the frame beneath the fan motor; a thin air pervious lower guard nested within the frame, driven by the step motor in the same direction as the fan blades assembly, but at much lower speed, and having radially spaced parallel vanes directing the downwardly flowing air in both axial and outwardly inclined, slowly revolving columns, for distributing the air over a wider area, while avoiding excessive air flow and "dead spots" beneath the fan; and a control mechanism including a separate switch for operating the step motor independently of t

Abstract: An arrangement for attaching a fan-fixture unit substantially flush with a ceiling includes first and second bowl shaped circular members with cylindrical rims. One of the members is fixedly attached to the ceiling electrical outlet box and the other to the top of the fan-fixture unit. One of the members includes a plurality of uniquely shaped slots and the other member a plurality of support rods, each accommodatable in a slot. To attach the unit, it is raisable by a single operator until the support rods are in the slots. Thereafter, the unit is rotatable and released, resulting in the rods being locked securely within particularly shaped portions of the slots.

Abstract: A hangar device for holding a recessed lighting fixture to a pair of beams utilizing a pair of elongated members movable in relation to one another. Each of the elongated members includes a shaft and an end piece angularly disposed in relation to the shaft. The end piece includes a lip fixed at an angle to the same and an end portion for fastening the pair of elongated members to each of the beams.

Abstract: A fan assembly has a main body support and a mounting member which are inclined at a predetermined angle thus permitting the fan assembly to be mounted either adjacent to the upper edge of a wall or in a corner of a ceiling. A rotating grill disperses a current of air over a relatively wide area. The main body support has a groove which accommodates a mating engageable member of the mounting member thus permitting the fan assembly to be securely mounted to a wall or a ceiling.

Abstract: A hanger for supporting an auger conveyor tube in a given angular position is provided. The hanger comprises a hanger element defining a hole for receiving the conveyor tube, and a number of recesses communicating with the tube hole. Each recess is adapted to mate with a tube flange, so as to locate the tube and a feed drop-out aperture in any of a first series of angularly discrete positions. A series of attachment holes at the hanger element top permit the hanger to be attached to support structure in any one of a second series of angularly discrete positions. In this way, a multiple series of angular positions is provided, so that the conveyor tube may be located in virtually any desired angular orientation.

Abstract: At anchoring in concrete, plugs and/or expanders are used; which require relatively deep holes for providing the strength required. In order to reduce the necessary hole depth without deteriorating the strength, and in general to facilitate and render cheaper the anchoring in concrete and other hard material, the present tensile force absorbing anchoring comprises an anchoring member formed integral of steel wire, with an anchoring portion located in a hole in the material, which portion comprises two gripping members, each with a free end engaging with the hole wall. The members are formed integral, with each of their two shanks abutting an opposed side of the hole wall against the engaging surface of the free end of the respective gripping member and extending axially out of the hole.

Abstract: A suspended ceiling, and components therefor, are described in which a carrying structure, for example in the form of carriers arranged in a grid, have depending therefrom a number of suspension units and a slat assembly, which may have decoratively disposed slats thereon, is mounted on each suspension unit. The arrangement is such that the slat assemblies are capable of at least limited rotation between a number of different positions, the slat assemblies being restrained in each position so that each slat assembly may have its orientation relative to its neighboring slat assemblies varied. This arrangement enables one to produce a very different visual effect simply by rotating certain of the slat assemblies relative to their neighbors. The specification discloses a number of different forms of slat assembly.

Abstract: Apparatus and method for changing the temperature of a room by moving warm air into or out of a room, and for effecting its distribution. A fan is removably and reversibly mountable on a bracket located on the upper portion of a doorframe in a manner which will not interfere with the normal operation of the doorway, and circulates air from one room into an adjacent room or hallway to effect a more even, efficient heating or cooling of living and work areas.

Abstract: A ceiling ventilation device, mountable in an opening in a ceiling between a pair of ceiling joists, includes a pair of mounting brackets. Each bracket, attachable at its ends to a pair of ceiling joists, includes a pair of spring biased mounting tangs spaced along the bracket. A housing defines an air intake opening and an air outlet opening and further defines, on each of two opposing sides thereof, a pair of tang receiving recesses spaced for alignment with and engagement by the tangs. A fan assembly, including a propeller assembly and a motor connected thereto, is mounted in the housing. Once the mounting brackets are connected to ceiling joists and positioned on opposite sides of an opening in a ceiling, the housing may be raised up into the opening such that the recesses in the housing are engaged by the tangs.

Abstract: A whole house ventillator which can be installed without framing and cutting joists. Struts below the fan blade serve as a support for a fan motor and for a venturi. Adjustable pre-cut sleeving fits over the joists and around the fan to eliminate framing. A shutter assembly may be surface-mounted to the ceiling below the joists.

Abstract: Arrangements for supporting a heat exchanger core within a steel frame structure by a hanger system utilizing flexible members pivotably coupled to overhead support beams. Balancing beams are employed to equalize the load transmitted through the system to the support beams. These support systems permit the heat exchanger core to expand in all directions from thermal growth without restraint relative to the frame structure, thereby minimizing thermal fatigue.

Abstract: A loop for leveling a hanging lamp. The loop has several notches for holding the lowermost link of a swag chain at several possible positions along the interior of the loop. The loop is then affixed to a lamp in a manner which permits turning it to any desired location so that a hanging lamp which would not hang straight if hung from its center may be made to hang straight by placing the lowermost link in a notch other than the center notch and rotating the loop to a position to correct the imbalance.

Abstract: A portable display device in the form of an open basket of a plurality of open grid members that is detachably supported by attached flanges to the horizontal support members of a suspended panel ceiling. The basket display device, when so mounted, furnishes a support to detachable hangar devices that may suspend display merchandise, signs or other items in a store, at any desired height and above any desired floor location. The device is preferably formed as an open basket and of the general horizontal size of an individual ceiling tile of the panel ceiling, with a vertical depth ranging from one to two inches.

Abstract: The present invention relates to an attachment clamp adapted to be mounted to a ceiling, such as a dry wall or acoustical tile ceiling, for structurally supporting a lighting fixture to the ceiling. The attachment clamp, which is formed of an integral resilient metal blank and a threaded adjustment member includes a foot portion adapted to be braced against the upper surface of the ceiling and a locking finger adapted to underlie the ceiling in spaced parallel relation to the foot portion, the threaded adjustment member being operable variably to space the foot and finger to clamp a thickness of ceiling between the two noted components.

Abstract: A lighting panel trim element for attachment to the outer marginal edges of a lighting panel is disclosed as having a throat section for receiving the top, side and bottom marginal edges of the lighting panel, a horizontal wall section for mounting the lighting panel relative to a lighting fixture, and means for positively securing the lighting panel within the throat section of the lighting panel trim element.

Abstract: A lighting fixture adapted to be mounted on a ceiling by attachment to an outlet box in the ceiling. The fixture comprises a pan having an upwardly extending rim and a crossbar attached to the bottom of the outlet box in a position extending horizontally across the bottom of the box. The rim of the pan is adapted to be attached to at least one end of the crossbar for mounting the pan adjacent the ceiling.

Abstract: The specification discloses a power pole assembly for bringing wiring through a hollow power pole from above and through a suspended grid supported ceiling is secured to a crossbar which in turn can be joined to spaced grid rails at any points along their length and at any angle with respect thereto by means of grid mounting clamps which can be releasably and movably joined to the rails and which are pivotally, movably and releasably secured to the crossbar. In this way, the power pole can be located at any position and at any angle relative to adjacent intersecting or parallel grid rails of the ceiling grid.

Abstract: A hanger bracket is disclosed for supporting and connecting sound absorption panels wherein the panels have a top frame member with a depending lip portion. The hanger bracket is usable for both fixed and movable sound absorption walls. The hanger bracket is comprised of two substantially identical bracket members having upper and lower generally vertical plates residing in offset substantially parallel planes. The bracket members are connected to each other, and to the support member, by connector means at the upper vertical plates. The lower plates have at least one punched-out tab portion extending generally inwardly then upwardly which engage the depending lip of the panel frame to thereby support the panel.The hanger bracket is attachable to both a fixed support member and to a movable trolley support member. A fixed sound absorption wall having one or more sound absorbing panels is provided wherein the hanger bracket supports the panels and is secured to a fixed support member.

Abstract: A ceiling hanger adapted to be removably installed on a horizontal supporting strip of a tile ceiling structure wherein tile panels are provided with edge portions resting on opposed edge portions of the supporting strip. The hanger includes a plate having a U-shaped end portion embracing one edge of the supporting strip, a midportion underlying the supporting strip, and a retaining clip embracing the opposite edge of the supporting strip and retaining the plate midportion juxtaposed to the underside of the supporting strip. The plate further includes a distal hanger portion which is bent downwardly about a connecting portion of the plate to provide a support such as for hanging an advertisement or the like from the ceiling supporting strip.

Abstract: A fluorescent lamp fixture having mounting brackets provided with keyhole-shaped openings for accommodating mounting screws. The mounting brackets have cover flaps for concealing the screws, and the flaps contain locking tabs for preventing dislodgment of the brackets from the screws.

Abstract: The suspension system is formed of a holder and a support member which is locked in the holder. The holder has a pair of shaped apertures which are disposed in opposed parallel relation which serve to receive constricted portions of the support member. The support member is fitted longitudinally into the apertures of the holder.

Abstract: A support for mounting an electrical outlet box in an aperture in a building panel, said support comprising a U-shaped yoke having a base portion, a pair of legs substantially normal to the base portion and a support foot extending outwardly from each leg substantially parallel to the base portion and adapted to overlie an area of the front of the building panel adjacent the aperture when the yoke is inserted in the aperture, each leg having at least one aperture intermediate the base portion and the foot; and a clamping member for association with each leg of the yoke, each clamping member having a support surface adapted to overlie an area of the back of the building panel opposite the area of the front of the building panel to be overlaid by the foot of the associated leg, a tab member extending from said support surface and adapted to interconnect the clamping member with said at least one aperture of the associated leg, and a clamping arm extending from the support surface on each side of the tab member,

Abstract: A light fixture mounting device is disclosed wherein a service outlet box has a mounting adaptor with light fixture suspension means providing temporary suspension of a light fixture during installation and connection of the electrical wiring and subsequent maintenance.

Abstract: In one exemplary embodiment, a construction clip for rigidly interconnecting and uniformly spacing a pair of ceiling inverted-tee support members defining an air conditioning air-slot through the ceiling is provided. Further, the clip provides support for the air conditioning ducts which carry air from the main air conditioning ducts to the air-slot. The clip, which is preferably formed of a high grade spring steel, includes an elongated body member having at each extremity a pair of legs extending normally upward from the body member and into a generally U-shaped configuration for securely gripping the vertical portion of the inverted-tee support members. The extremities of each leg are inwardly bent to form clasping hook ends for tightly gripping the tee member vertical portion in a sliding relation. Each pair of legs defines a slot therebetween which extends from the body member to the extremities of the legs to enable the clip to be positioned over intersecting tee members.

Abstract: A light fixture support is provided comprising a support bar having slots at the extremities which cooperate with inverted "T" members forming the framework for a conventional suspended ceiling to adjustably locate and secure a light fixture within the framework. The slot configuration defined by the light fixture support permits the enlarged extremity of the upstanding portion of the "T" member to be rotated for insertion within the slot, returned to a vertical position, and retained within the slot. If desired, an adjustable support may be provided for accommodating a variety of "T" member spacings or for compact packaging with a light fixture.

Abstract: A hold-down and retaining clip for a lay-in light fixture secures the fixture to the T-bar frame of the suspended ceiling against both vertical and lateral movement. The main body portion of the clip has an L-shape configuration adapted to lie substantially adjacent the stem in one bottom flange of the T-bar. The upper vertical leg of the clip includes an extended center portion which is formed in an enlarged bend extending over the top of the stem with substantial clearance and terminates in an upwardly rebent edge adapted to engage the far side of the stem. The shorter lateral portions of the vertical leg have their upper edges bent toward the stem and are adapted to engage the near side of the stem at a slightly higher elevation than the terminal edge on the far side of the stem.

Abstract: An integrated suspension ceiling and recessed lighting fixture system is disclosed in which a fixture is supported primarily on arched bridging members which extend between parallel runs of the grid of the suspension ceiling. The bridging members lock at their ends in the runs and maintain a predetermined spacing between the runs thus permitting relatively long uninterrupted fixtures to be installed in the suspension ceiling. The bridging members also support a continuous channel or raceway which permits the fixture to be wired as a unit regardless of its total length. A reflector is supported by flanges of the inverted tees constituting the runs along the sides of the fixture so separate framing is not required. With the invention recessed lighting fixtures of substantially any desired length may be installed in a suspension ceiling system.

Abstract: A clip assembly is disclosed for suspending objects from conventional track railings employed for supporting ceilings of the panel type. The clip has oppositely disposed side walls which are joined at one end and which have oppositely disposed end portions projecting inwardly from the free ends of said side walls. The end portions have a flat inner surface which, when slid on or snapped over the track railing, engage the flat surface of the track railing to thereby enable considerable weight to be suspended from a recess in a web integrally formed with said side walls.

Abstract: A recessed lighting fixture which can be mounted in a wall or ceiling and requires a minimal opening for insertion. After the lighting fixture has been secured in the opening, normally no plastering or refinishing is required. A plurality of fasteners are positioned on the interior of the fixture housing. The fasteners are each mounted on a screw. A slot enables each of the fasteners to be rotated to the exterior surface of the housing after the lighting fixture has been positioned in the ceiling. The length of each fastener is greater than that of its corresponding slot. When the screw is rotated the securing member is positioned on the exterior of the lighting fixture housing. Further rotation of the screw causes the fastener to move to a position where it is adjacent the top surface of the ceiling and the lighting fixture is premanently secured to the structure.

Abstract: A fixture support for a grid-type ceiling, comprising spaced clip means adapted for mounting on spaced, generally parallel, inverted T-shaped, in cross section, grid bars, with the clips having a plurality of vertically spaced openings therein for mounting a bridging bar therebetween, the bridging bar having hanger means mounted thereon for suspending a fixture, such as an electrical outlet box therefrom, and with the vertically spaced openings on the clip providing for selective vertical positioning of the bridging bar and associated hanger means with respect to the clips, thereby varying the vertical position of the outlet box with respect to the ceiling grid.

Abstract: Suspended ceiling systems are formed from a series of modules which may have a vaulted design and a light fixture therein. These modules must be supported from the main runners or cross tees of a suspended ceiling system. The support structure herein is fastened at one end to the main runners or cross tees of the suspended ceiling system and carry on their other end the main horizontal support members for the light fixture and vaulted module. Means positively lock the support structure to the main runner or cross tee of the suspended ceiling system.

Abstract: Suspended ceiling systems are formed from a series of modules which may have a vaulted design and a light fixture therein. These modules must be supported from the main runners or cross tees of a suspended ceiling system. The support structure herein is fastened at one end to the main runners or cross tees of the suspended ceiling system and carry on their other end the main horizontal support members for the light fixture and vaulted module.

Abstract: A shelf couple assembly for mounting shelves on walls, wall studs, or rafters utilizes a unitary shelf-gripping couple having a protruding cantilever platform with raised rearward and forward portions and downwardly projecting barbs for fixedly supporting a shelf board between these raised portions and barbs. The assembly also incorporates a shelf trim channel that is snapped onto adjoining shelf boards to align them and to provide a visually unitary appearance. Furthermore, the assembly incorporates a rear shelf clip which may be driven into a wall-board, stud, or rafter for supporting the rearward portion of two adjoining shelf boards or for adding support to a section of shelf board that is heavily loaded. In addition, a cover is incorporated in the assembly that fits over the unitary shelf couple and thus conceals it while enhancing the overall appearance of the shelf couple assembly.

Abstract: A method and girder structure for attachment of ceiling-suspended equipment in operating theatres, X-ray-and examination rooms with joists and intermediate ceiling in hospitals, clinics and surgeries, a permanent load-carrying structure being attached to the ceiling of the room, a girder structure which is broad in relation to its height being attached to the joists, with its lower edge flush with the intermediate ceiling, said structure being provided with pipes and ducts for gases, fluids and exhaust in one channel and electric cables in another channel, an equipment for operating table lighting, anaesthesia, artificial ventilation, surgical distribution boards and X-ray equipment being displaceably secured to the girder structure which is also used for joint earthing of the ceiling-suspended equipment.

Abstract: A mounting device, particularly for ceiling or wall fittings, comprising a first member adapted to engage a means of attachment provided in a mounting surface by means of a fastening device whereby said first member will bear against said mounting surface, and a second member having means for engagement with a complementary attachment device of said first member said fastening device having a groove provided in said first member and inclined in relation to said mounting surface to gradually engage said means of attachment when said first member is being secured to said mounting surface.